Although microplastics (MP) and human health is an emerging field many studies have now highlight the potential of these products as an increasing health hazard. If inhaled or ingested, microplastics may accumulate and exert localized particle toxicity by inducing or enhancing an immune response. Chemical toxicity could occur due to the localized leaching of component chemicals and pollutants. Chronic exposure is anticipated to be of greater concern due to the accumulative effect that could occur and is expected to be dose-dependent. That is the more you are exposed to over a longer period the more serious the health consequences.
Animal studies have shown a variety of toxic effects from microplastics including clogging of the digestive tract and a feeling of fullness, along with internal injuries, such as a perforated gut, ulcerative lesions, or gastric rupture, potentially leading to death and intestinal alterations. Just as importantly anyone that ingests MPs are exposed to a large variety of chemicals, including additives added to plastic during manufacture and pollutants. Plastic additives are plasticizers (phthalates, bisphenol A, etc.) colorants, UV filters, flame retardants, etc. As well as pollutants (PCBs, organochlorine pesticides, PAHs, etc.) and metals can also be absorbed onto the surface of plastic debris during their transfer into aquatic environments. The resulting biological consequences can compromise our health particularly early on in life.
Transfer of microplastics into food webs and environments including all different aquatic and terrestrial environments. Microplastics have been detected in more than 200 different species and food products that are part of the human food chain and have found in seafood products and in other foods and beverages such as beer, honey and even table salt. As I already highlighted in our first blog on microplastics plastic water bottles are a major source for many individuals. Individuals who meet their recommended water intake through only bottled sources may be ingesting an additional 90000 microplastics annually, compared to 4000 microplastics for those who consume only tap water.
Unfortunately, our pets are also frequently exposed to microplastics. Our pets are often are sentinels of human exposure, as they share a common living environment with humans. In one study they found extensive contamination of polyethylene terephthalate (PET) in cat and dog foods which accounted for just under half their exposure.
Environ Sci Technol. 2019 Oct 15;53(20):12035-12042. doi: 10.1021/acs.est.9b03912. Epub 2019 Sep 26. Polyethylene Terephthalate and Polycarbonate Microplastics in Pet Food and Feces from the United States. Zhang J1,2, Wang L2, Kannan K1.
Environ Sci Technol. 2019 Jun 18;53(12):7068-7074. doi: 10.1021/acs.est.9b01517. Epub 2019 Jun 5. Human Consumption of Microplastics. Cox KD1,2, Covernton GA1, Davies HL1, Dower JF1, Juanes F1, Dudas SE1,2,3.
Environ Toxicol Pharmacol. 2019 May;68:75-79. doi: 10.1016/j.etap.2019.03.007. Epub 2019 Mar 8. Food Addit Contam Part A Chem Anal Control Expo Risk Assess. 2019 May;36(5):639-673. doi: 10.1080/19440049.2019.1583381. Epub 2019 Apr 15. Review of micro- and nanoplastic contamination in the food chain. Toussaint B1, Raffael B1, Angers-Loustau A1, Gilliland D1, Kestens V1, Petrillo M1, Rio-Echevarria IM1, Van den Eede G1.